Could you recommend any suitable Studio Monitors that are ideal for home DJing and production work for use with Har-Bal? Are Mackie and Tannoy good suitable speakers? What should I be looking for in studio monitors?
For mastering monitors, you should be looking for speakers with good imaging and preferably a uniform and controlled frequency response from 50Hz up to 20kHz. You can get away with smaller sized speakers as monitors but you have to be very careful about what you do at the low frequency end of the spectrum with bookshelf speakers : They usually just don’t have any useful output below 80-90Hz which can lead to muddy sounding mixes if you happen to play your recording on a system that does reproduce down to 50Hz.
The brand names you mentioned are extremely capable models. Probably the most important thing is to know the sound of your speakers and to do this you need some reference material that you know well enough to know what it sounds like. Then just use this to evaluate each speaker you try out. Probably the easiest way to get an idea of the way it should sound (if you don’t have someone’s monitors as a reference) is through a good quality pair of headphones (Sennheiser for example). But beware that the way things sound in headphones is somewhat different than with speakers (mainly the imaging). Just concentrate on the tonality.